Disazo dyes.



UNITED sra'rns anew canton ALBERT GLAUSIU'S, 0F DESSAU IN ANHALT, BERNI-IARD SCHNEEt, 0F BABAGKENLAGER ROTI-IEMARK, NEAR WITTENBERG, AND OTTO SIEBEBT, 6F DESSAU IN ANHALT, GERMANY, ASSIGNOBS T0 ACTIEN GESELLSCHAFT EU'R ANILIJSI FABRIKATION, OF

BnnLinr, GERMANY.

1,213,075. No Drawing.

many, Barackenlager Rothemark, near Wittenberg, Germany, and Dessau in Anhalt, Germany, have invented certain new and useful Improvements in the Manufacture of DISAZO DYESL Specification of Letters Eatentl i Pat gnted Jan, 1(5, 1917, Application filed August as, leis. Serial at. 117,105. a

DisazoDyes, of which the following is a specification.

This invention relates to new disazo dyes which derive from a derivative of Q-aminophenol containing the nitro group, 2-amino- 5-naphthol-7-sulfonic acid and an alkylaralkyl-arylamin sulfonic acid and correspond to the general formula:

Alkyl where .R means a radical of the benzene series substituted or not. These new dyes in the shape of pulverized dry sodium salts are blackish powders, soluble in water with a violet color changing to red by ammoniumor sodium-hydroxid. The aqueous so- '2 lution becomes reddish on addition oi hydrochloric acid and the dye separates.

Con centrated sulfuric acid dissolves the dyes to green solutions, the addition of ice changes the color over blue and violet to reddish-and effects the precipitation of the dyes. vStrong reducing agents destroy the "dyes yielding a diaminophenol-compound,

2.6-diamino-5-naphthol-7-sulfonic acid and an. aminoaryl-alkyl-aralkylamin sulfonic acid.

The new dyes furnish on Wool from an I acid bath violet tints which by a treatment with a suitable chromium compound, such as alkali metal b'ichromate, turn to black shades of an excellent fastness to light, td

Washing and to millin In order illustrate in which manner the dyes may be manufactured, Without limiting the invention, the following examples are given, the parts being by Weight:

1. 15.4: parts of i-nitro-Q-aminophenol are diazotized by means of 50 parts of hydroohioric acid; of 12 Be. and 6.9 parts of sodium nitrite and combined with 24 parts or". 2-aniino-5-naphthol-7-sulfon1c acid in the presence of sodium carbonate. The

separated intermediate product issuspended and 40 parts of calcined sodium carbonatein- 500 parts or" Water. When the reaction is complete the disazo dye is salted out and dried, Its constitution in the free state may be given by the formula:

presence of sodium carbonate. The intermediate product is acidified. with hydrochloric acid and during 3 hours diazotized at 0 C. with 30 parts of hydrochloric acid iEST AVAILABLE COP.

of 12 Be. and 7 parts of sodium nitrite.

Then the combination is eltected with 30 parts of ethylbenzylanilindsultonic acid, dissolved with parts ofcalcined sodium III In the foregoing examples as startingmaterials for instance -'Hl-dinitro-ii-aminophenol' or (i-nitro-2-aminophenol r-sulfonic acid may be used. Instead of ethylbenzylani.lin-4'-sult'onic acid with the same effect methyibenzylanilin--l-sulfonic acid may be used.

Having now descrlbed our invention and where R means a radical of the benzene series substituted or not: in the shape of pulverized dry sodium salts being blackish powders soluble in water with a violet color changing to red by ammoniumor sodiumhydroxid; the aqueous solution becoming reddish and separating the dye when acidified by hydrochloric acid: soluble in concentrated sulfuric acid to green solutions which on addition of ice change the color over blue and violet to reddish the dyes being precipitated; being destroyed by strong: reducing in the shape of pulverized dry sodium salt being a blackish powder, soluble in water with a violet color changing to red by am moniunr or sodium-lrvdroxal: the aqueous solution becomin; reddish and separating the dye when acidified by lrvdrochloric acid: soluble in, concentrated sulfuric acid to a green solution which on addition of ice changes the c lor over blue and violet to redd sh, the dye being precipitat d; being destroyed by strong realucing' agrents yieldin; 2.l :Iiamiuopbenoh QJS-diamiuo 11mphtliol'T-sldi'ouic ar d and Laminoaryl-rrhvlcarbonate in 600 parts of water. The disazo dye is worked as usual. The following formula indicates its constitution in the free state:

the manner in which it may be carried out what we claim is,-

1. The new disazo dyes which derive from a,dcrivativc of Q-aminophcnol containing the intro-group, 2-amino-fi-naphthol-7-sul-v tonic acid and alkyl-arall yl-arylamin-sultome acid and correspond to the general formula Alkvl agents yielding a diaminophenol compound, LG-(haiuino-5-1mpl'ithol-7-sultonic acid and an aminoanvl alkyl aralkylamin snlfonic acid: dyein; wool from an acid bath violet tints which by a treatment with an alkali metal bichromate turn to black shades.

The new disazo dye which derives from lnitro-Z-aminophenol. 2-11n'iino-fi-mlphthol- T-sulfonic acid and ethylbenzylanilin-l-"sulfonic acid and probably correspomls to the formula: 

